Coaxial cables are commonly utilized in RF communications systems. A typical coaxial cable includes an inner conductor, an outer conductor, a dielectric layer that separates the inner and outer conductors, and a jacket that covers the outer conductor. Coaxial cable connectors may be applied to terminate coaxial cables, for example, in communication systems requiring a high level of precision and reliability.
Coaxial connector interfaces provide a connect/disconnect functionality between (a) a cable terminated with a connector bearing the desired connector interface and (b) a corresponding connector with a mating connector interface mounted on an apparatus or on another cable. Typically, one connector will include an inner contact, such as a pin or post connected to an inner conductor and an outer conductor connector body connected to the outer conductor; these are mated with a mating sleeve (for the pin or post of the inner conductor) and another outer conductor connector body of a second connector. Coaxial connector interfaces often utilize a threaded coupling nut or other retainer that draws the connector interface pair into secure electro-mechanical engagement when the coupling nut (which is captured by one of the connectors) is threaded onto the other connector.
Passive Intermodulation Distortion (PIM) is a form of electrical interference/signal transmission degradation that may occur with less than symmetrical interconnections and/or as electro-mechanical interconnections shift or degrade over time. Interconnections may shift due to mechanical stress, vibration, thermal cycling, and/or material degradation. PIM can be an important interconnection quality characteristic, as PIM generated by a single low quality interconnection may degrade the electrical performance of an entire RF system. Thus, the reduction of PIM via connector design is typically desirable.
A new proposed 4.3/10 interface under consideration by the IEC (46F/243/NP) (hereinafter the 4.3/10 interface) is alleged to exhibit superior electrical performance and improved (easier) mating. The 4.3/10 interface includes the following features: (a) separate electrical and mechanical reference planes; and (b) radial (electrical) contact of the outer conductor, so that axial compression is not needed for high normal forces. The alleged benefits of this arrangement include:                Increased mechanical stability, as the mechanical reference plane is now outside the RF path;        Non-bottoming of the electrical reference plane (as contact is made in the radial direction)—therefore, normal (radial) forces are independent from coupling nut torque applied;        Coupling nut torque reduction;        Improvement in PIM performance as outer contact radial forces are independent of coupling nut torque applied; and        Gang mating of several connectors as the electrical reference plane can float (axially). Therefore, tolerance stack-ups from connector to connector should have no effect.        
It may be desirable to provide additional versions of connectors that meet the 4.3/10 interface standard and also address other performance issues like PIM reduction.